Error when updating SQL table with Pyodbc from data extracted from Excel spreadsheet

Question

When running the following Python 2.7 script, I am getting a pyodbc.Error. The Excel spreadsheet I am using has 4 lines in it.

import pyodbc
from mmap import mmap,ACCESS_READ
import xlrd
import os

#for row_index in range(1,sheet0.nrows):

cnxn = pyodbc.connect('driver={DB};NetworkAddress=DB_Address,Port;Db=DB;uid=login;pwd=password')
cursor = cnxn.cursor()

book=xlrd.open_workbook("I:\\CNLD.xlsx")
sheet=book.sheet_by_index(0)
cell=sheet.cell(1,1)

for rownum in range(sheet.nrows):
    print sheet.row_values(rownum)

print sheet.nrows 

update_dyna = "insert into tempdb..cm_dyna(secsym,pvsym,min_bid_off,min_bid_offpt,min_ask_off,min_ask_offpt,max_bid_off,max_bid_offpt,max_ask_off,max_ask_offpt) values(?,?,?,?,?,?,?,?,?,?)"

for row_index in range(1, sheet.nrows):
    row_num         = row_index
    secsym          = sheet.cell(row_index,0).value
    pvsym           = sheet.cell(row_index,1).value
    min_bid_off     = sheet.cell(row_index,2).value
    min_bid_offpt   = sheet.cell(row_index,3).value
    min_ask_off     = sheet.cell(row_index,4).value
    min_ask_offpt   = sheet.cell(row_index,5).value
    max_bid_off     = sheet.cell(row_index,6).value
    max_bid_offpt   = sheet.cell(row_index,7).value
    max_ask_off     = sheet.cell(row_index,8).value
    max_ask_offpt   = sheet.cell(row_index,9).value
    values = (secsym,pvsym,min_bid_off,min_bid_offpt,min_ask_off,min_ask_offpt,max_bid_off,max_bid_offpt,max_ask_off,max_ask_offpt)
    cursor.execute(update_dyna,values)    

cursor.close()
cnxn.commit()
cnxn.close()

Here is the error message that is getting kicked out:

cursor.execute(update_dyna,values)    
pyodbc.Error: ('HY000', '[HY000] [DataDirect][ODBC Sybase Wire Protocol driver]Data type for parameter 2 has changed since first SQLExecute call. (0) (SQLExecDirectW)')

cursor.execute is a part of the loop, so I am not sure why I am not able to update a spreadsheet that has 4 lines in it.

Answer 1

The error message is telling you that you've got a different data type between one call to cursor.execute and then next - and that Sybase doesn't allow this.

A quick workaround may be to commit the transaction inside the loop. I don't have Sybase handy to test this.

Alternatively, force your data into the correct format. I suspect you've got a mix of strings, ints, and floats. But you can force it something like:

min_bid_off     = float(sheet.cell(row_index,2).value)